PROJECT SUMMARY This proposal is motivated by the following observations: 1) Fluid intake is a safe and effective method to reduce urinary stone recurrence, but adherence is low; 2) Ureteral stents cause pain for many patients despite pharmacologic treatments; 3) Behavior- the way that we respond to a situation or stimulus- is a critical determinant of treatment adherence and the perception of pain; and 4) Behavioral economics and complementary theories of behavioral coping provide conceptual frameworks to decrease stone recurrence and stent pain among children and adults with urinary stone disease (USD). Barriers to increasing fluid intake among patients with USD include limited knowledge about sufficient fluid volume, difficulty maintaining long-term engagement in meeting fluid goals, and inability to solve logistical problems such as ready access to fluids at work or school. Therefore, a customized program of structured problem solving (SPS), a systematic approach to identify the root cause of a problem and develop a feasible solution, is needed. However, SPS alone may be insufficient. People are often motivated more by tangible, short-term rewards - such as financial incentives - than by the possibility of health benefits realized only later in time. This observation is relevant for USD, because the short-term benefits of fluid intake may not be apparent since USD episodes commonly take place after months or years without symptoms. Financial incentives can overcome present bias and are a novel approach to increasing fluid intake to prevent stone recurrence. Most patients with ureteral stents experience pain of varying intensity. This pain is often refractory to medications, suggesting that factors other than biologic responses account for a large portion of symptoms. Preoperative anxiety is associated with increased postoperative pain. Patients who catastrophize have reduced ability to modulate pain due to excessive attention to pain (rumination), exaggerating the threat value of pain (magnification), and feeling unable to cope (helplessness). Behavioral coping theory can be applied to predict which patients will have intensified pain responses during procedures or following surgery. Accurately predicting which patients are will have increased pain from ureteral stents could help identify those who would benefit most from preemptive targeted cognitive and behavioral interventions to decrease pain. As part of the Urinary Stone Disease Research Network, we propose to conduct a randomized controlled trial among adults and adolescents with USD to determine the efficacy of SPS, versus SPS combined with financial incentives for meeting fluid intake goals, versus control to decrease symptomatic stone recurrence. Second, we will conduct a prospective cohort study among adolescents and adults with USD who undergo ureteral stent placement and identify psychological characteristics that predict increased pain due to ureteral stents. Finally, we will establish a repository of urine and blood from these patients to support future USD research. The long-term goal of the proposed studies is to reduce the morbidity of USD.